MAO inhibition and control of anxiety following amitriptyline therapy. A pilot study

In a pilot study, 32 patients with mixed states of anxiety, depression, somatization and panic received amitriptyline for 4 weeks, the dose ranging from 50 to 300 mg/day. Steady-state plasma levels of the drug and activity of platelet monoamine oxidase were measured after 4 weeks. Clinical change was rated, using the SCL-90. Amitriptyline produced a small but significant inhibition of platelet monoamine oxidase activity (range 1.4--82%). A significant positive correlation was noted between MAO inhibition and improvement on somatization, and psychological and panic-phobic components of anxiety, but not for depression. No significant correlations were observed between improvement and combined or separate ami- + nortriptyline plasma levels.